Iodine and thiocyanogen numbers for unsaturated compounds of various types have been determined by the Hanus solution (one and two hours) and Kaufmann solution (forty-seven hours), respectively. The results are discussed in connection with the general question of the effect of negative groups in the vicinity of the ethylene bond in hindering the addition of the halogen and halogenoid. Such a hindrance is evident. The effect decreases with the ...
